DESCRIPTION (Investigator's Abstract) "This is an application to become a participating Clinical Center in the Ocular Hypertension Treatment Study (OHTS). The complete details of the OHTS rationale, design, and methods are contained in the OHTS Manual of Procedures. This proposal provides complete documentation of the ability of The New York Eye and Ear Infirmary to participate as an effective and productive Clinical Center in the OHTS and to enroll at least fifty eligible patients over a 24-month period, based upon pilot studies of patient eligibility. Documentation is provided of the capabilities of the proposed investigators and their staff for the performance of the study in accord with the details of the OHTS Manual of Procedures and the nature and extent of their commitment to the New York Eye and Ear Infirmary. Details are provided of plans to identify, recruit, follow, and retain these patients, our intent to obtain consistently high quality data of the visual outcomes, record and transfer study data to the Coordinating Center, contribute to reports that will present the OHTS results, and the personnel and facilities available within our center to carry out the provisions of the OHTS's Manual of Procedures."